Spring charging actuating mechanism for an electric switching device

ABSTRACT

In an actuating mechanism for an electric switching apparatus such as an electric circuit breaker or the like there is provided first and second springs for respectively storing the energy needed for closing and the energy needed for opening the apparatus. The actuating mechanism further has a tensioning device for tensioning the spring as well as a housing for receiving the tensioning device therein. An improved mounting arrangement of the actuating mechanism includes first and second shafts mounted in the housing so as to have respective endportions projecting from the housing. The springs are disposed outside the housing and have respective ends anchored to the housing. The other end of the first spring and the other end of the second spring are connected to the end-portion of the first shaft and to the end-portion of the second shaft respectively so as to coact therewith.

nited States Patent 1191 Liebig et al.

1 51 Aug. 5, 1975 1 1 SPRING CHARGING ACTUATING MECHANISM FOR AN ELECTRIC SWITCHING DEVICE [75} Inventors: Reinhard Liebig; Siegfried Jfihrig;

Werner Kiigler, all of Berlin,

21 Appl. No.: 376,941

[30] Foreign Application Priority Data July 24, 1972 Germany 2236788 [52] US. Cl. 200/153 SC; 185/40 R [51] Int. Cl .1 HOlh 3/30; F03g 1/08 [58] Field of Search 200/153 G, 153 H, 153 SC; 335/76; 185/40 R Wilson 200/153 SC X 3,773,995 11/1973 Davies 200/153 sc 3,806,684 4/1974 Hauser 185/40 B x FOREIGN PATENTS OR APPLICATIONS 1,515,535 9/1969 Germany 200/153 sc Primary E.\'aminer.lames R. Scott Attorney, Agent, or FirmKenyon & Kenyon Reilly Carr & Chapin [57] ABSTRACT In an actuating mechanism for an electric switching apparatus such as an electric circuit breaker or the like there is provided first and second springs for re spectively storing the energy needed for closing and the energy needed for opening the apparatus. The actuating mechanism further has a tensioning device for tensioning the spring as well as a housing for receiving the tensioning device therein. An improved mounting arrangement of the actuating mechanism includes first and second shafts mounted in the housing so as to have respective end-portions projecting from the housing. The springs are disposed outside the housing and have respective ends anchored to the housing. The other end of the first spring and the other end of the second spring are connected to the end-portion of the first shaft and to the end-portion of the second shaft respectively so as to coact therewith.

4 Claims, 3 Drawing Figures PATENTEU AUG 5 I975 SHEET PATENTEU AUG 5|975 SHEET SPRING CHARGING ACTUATING MECHANISM FOR AN ELECTRIC SWITCHING DEVICE BACKGROUND OF THE INVENTION For switching apparatus of a definite function and operating capacity, a construction has been introduced having separate pole columns for the individual switching locations and which includes a housing wherein the actuating mechanism for the switching columns is located. The switching apparatus can for example be mounted to the wall of ahousing or it can be secured to a frame. It is customary to use this construction especially for high-voltage power circuit breakers of the oilpoor type and which are operable at voltages of for example 6 to KV.

Up to the present time efforts have been directed to accommodate in the housing all elements needed to operate the actuating mechanism, and to only make control members accessible from the outside.

SUMMARY OF THE INVENTION It is an object of the invention to provide an improved mounting arrangement of the actuating mechanism for switching apparatus of the above-mentioned type which will facilitate the adaptation of the actuating mechanism to different types of switching apparatus. For example, with the invention, the actuating mechanism can be adapted to switching apparatus of high or lower switching capacity and therewith more or less energy requirements for the switching operations.

The invention then is based on an actuating mechanism for electric switching apparatus such as electric power circuit breakers or the like. The actuating mechanism is equipped with first and second springs for respectively storing the energy needed for closing and the energy needed for opening the apparatus, a tensioning device for tensioning the springs, and a housing for receiving the tensioning device therein as well as bearing shafts needed to switch the apparatus.

The improved mounting arrangement of the actuating mechanism includes as a feature that first and second shafts of the tensioning device are mounted in the housing so as to have respective end-portions projecting from the housing. The springs are disposed outside of the housing and have respective ends anchored to the housing. The other end of the first spring and the other end of the second spring are connected to the endportion of the first shaft and to the end-portion of the second shaft respectively so as to coact therewith.

With this improved mounting according to the invention, a substantially simpler access to the usually relatively large and difficult-to-manipulate springs (coil springs, tension-applying or pressure-applying springs) is obtained during assembly.

If for the above-mentioned housing there is chosen the usual proportions of its sides, with which the depth is less than the edge-lengths of the front and rear sides, there is obtained a favorable form of construction, if the springs for storing the switch-closing and switchopening energy are disposed outside the narrow sides of the housing. The coaction of the springs with the shafts of the operating mechanism is then possible in the same way as with the conventional disposition of the springs inside the housing. The new arrangement however offers the advantage of protection against damage, because the springs, being outside the housing, are accessible for inspection and maintenance work. The invention moreover gives a favorable arrangement for the bearings for the shafts which decreases the stress on the bearings.

According to another embodiment of the invention, the shaft for the switch-closing spring can be disposed at a greater distance from its point of suspension than the shaftfor the switch-opening spring. This gives a larger installation space for the switch-closing spring. The disposition of the springs in the general structure of the switching apparatus is also convenient, because the housing for the actuating mechanism can now be kept narrower, and thus the overall width of the switching apparatus is not altered.

The invention is especially suited for medium-voltage power breakers of the oil-poor type. A circuit breaker of the oil-poor type is one wherein a jet of oil is generated at the breaking gap which quenches the arc occurring during breaker opening operations.

Although the invention is illustrated and described herein as AN IMPROVED MOUNTING ARRANGE- MENT OF AN ACTUATING MECHANISM FOR ELECTRIC SWITCHING APPARATUS, it is nevertheless not intended to be limited to the details shown, since various modifications may be made therein within the scope and the range of the claims. The invention, however, together with additional objects and advantages will be best understood from the following description and in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING The drawing shows, in schematic perspective, the improved mounting arrangement according to the invention for an actuator mechanism suitable, for example, for actuating a three pole power circuit breaker. The drawing emphasizes those portions of the actuator mechanism needed for an understanding of the improved mounting arrangement according to the invention. More specifically, the drawing includes:

FIG. 1 as a schematic perspective diagram illustrating an actuator mechanism equipped with the improved mounting arrangement according to the invention; this view shows the actuator mechanism in its open position wherein the closing spring is tensioned and the opening spring is relaxed;

FIG. 2 is also a schematic perspective diagram showing a pertinent portion of the actuator mechanism to illustrate the closed position wherein both springs are tensioned; and,

FIG. 3 likewise shows the closed position wherein, however, the closing spring is again tensioned preparatory for a new switching operation.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION Referring to FIG. l, the housing I of the actuating mechanism is made from sheet metal and bent to have a U-shape. The legs Zand 3 of the U-shaped housing 1 are provided with outwardly directed bent portions which provide reinforcement for securing the breaker and for accommodating a cover. Two mutually parallel carrier rails 7 and 10 are mounted on the center portion 6 of the housing 1; these rails 7 and 10 have bores 8 and 9 for securing the switching poles one of which is shown in the drawing and designated by reference numeral 31. Additional bores II and 12 are provided for mounting the breaker.

A carrier rail 13 is mounted in the legs 2 and 3 of the housing 1 and serves to reinforce the same. The outwardly extending end-portions 15 and 14 of the rail 13 serve to anchor a breaker closing spring 16 and a breaker opening spring 17, respectively. The closing spring 16 coacts with crank-arm 20 fixedly mounted on the outwardly extending portion of spring winding shaft 21. Above shaft 21, a switching shaft 22 is mounted in the legs 2 and 3 which likewise has an outwardly extending end-portion provided with a crank-arm 23. The breaker opening spring 17 coacts with the crank-arm 23. A larger installation space is provided for the breaker closing spring 16 by the arrangement of the spring-winding shaft 21 beneath the switching shaft 22.

FIG. 1 illustrates the actuating mechanism in the open position of the breaker which corresponds to the operational ready position wherein the closing spring 16 is tensioned. To move the breaker to the closed position, the closing magnet 26 is actuated for releasing a latching arrangement (not illustrated) of the shaft 21. Under the influence of the closing spring 16, the shaft 21 moves through a one half rotation and thereby moves'the shaft 22 by means of a cam disc 37 and a crank arm 41 provided with a roller 40. In this way, the switching pole 31 is actuated through a crank arm 32 and a coupling rod 33 while at the same time, the breaker opening spring 17 is tensioned by means of the crank arm 23.

The crank arm 23 mounted on shaft 22 then takes on the position shown in FIG. 2. The parts remain in the position shown in FIG. 2 for only a short time because in the lower position of the crank arm, the unit 24 is closed through self action. The unit 24 rotates shaft 21 stepwise by means of a push crank 34 and a push pawl 35 which engages the ratchet wheel 36'until the shaft 21 reaches the position corresponding to FIG. 3 thereby tensioning the closing spring 16. The breaker closing spring 16 stores the energy needed for closing the switching pole 31 and additional switching poles (not illustrated) as well as the energy for tensioning the opening spring 17.

For opening the breaker, an additional latching arrangement (not shown) is released by actuating the breaker opening magnet 27 thereby releasing shaft 22. The shaft 22 then opens the switching pole 31 by means of the crank arm 32 mounted on shaft 22 and the coupling rod 33. The position then occupied by the parts is shown in FIG. 1 wherein the breaker closing spring 16 is tensioned and the breaker opening spring 17 is relaxed.

The drawing shows that the total width of the actuathe unit 24 and are assembled in a block. An electrounits 30 is provided beneath the electromagnet 26 and the additional unit 27.

What is claimed is:

1. In an actuating mechanism for an electric circuit breaker equipped with at least one switching pole, said mechanism including first and second springs for respectively storing the energy needed for closing and the energy needed for opening the apparatus, a tensioning device for tensioning the springs and including first and second shafts having respective end portions, and a housing for receiving the tensioning device therein, the housing including mutually adjacent narrow side walls for accommodating the first and second shafts of the tensioning device thereon, wherein the improvement comprises the first and second shafts mounted in said housing so as to cause the end-portions of the first and second shafts respectively to project from said housing, said first and second springs being disposed outside of said housing and having respective one ends, and anchor means for anchoring said one ends of said springs to the housing at respective anchor locations, the other end of the first spring being connected to said endportion of said first shaft so as to coact therewith and the other end of the second spring being connected to the end-portion of said second shaft so as to coact therewith, said first shaft and said anchor means conjointly supporting said first spring adjacent the outer side of one of said side walls, and said second shaft and said anchor means conjointly supporting said second spring adjacent the outer side of the other one of said side walls whereby said springs are arranged outside of the housing thereby rendering said springs accessible for inspection and maintenance work, the housing further including a center wall connecting the mutually adjacent narrow side walls and, two mutually parallel carrier rails to which the breaker and the switching pole can be securely mounted, said carrier rails being mounted on said center wall.

2. In an actuating mechanism for an electric switching apparatus such as an electric circuit breaker or the like, said mechanism including first and second springs for respectively storing the energy needed for closing and the energy needed for opening the apparatus, a tensioning device for tensioning the springs and including first and second shafts having respective end portions, and a housing for receiving the tensioning device therein, the housing including mutually adjacent narrow side walls for accommodating the first and second shafts of the tensioning device thereon, wherein the improvement comprises the first and second shafts mounted at fixed locations in said housing so as to cause the end-portions of the first and second shafts respectively to project from said housing, said first and second springs being disposed outside of said housing and having respective one ends, and anchor means for anchoring said one ends of said springs to the housing at respective anchor locations, the other end of the first spring being connected to said end-portion of said first shaft so as to coact therewith and the other end of the second spring being connected to the end-portion of said second shaft so as to coact therewith, said first shaft and said anchor means conjointly supporting said first spring adjacent'the outer side of one of said side walls, andsaid second shaft and said anchor means conjointly supporting said second spring adjacent the outer side of the other one of said side walls whereby said springs are arranged outside of the housing thereby rendering said springs accessible for inspection and said first distance being greater than said second dismaintenance work. tance.

In h actuatmg fnechamsmPf Sa 1d first 4. In the actuating mechanism of claim 3, wherein shaft being mounted in the housmg at a first distance from the anchor location of the first spring, and Said 5 said anchor locations of said springs are at the same elsecond shaft being mounted in the housing at a second evation on Said housingdistance from the anchor location of the second spring, 

1. In an actuating mechanism for an electric circuit breaker equipped with at least one switching pole, said mechanism including first and second springs for respectively storing the energy needed for closing and thE energy needed for opening the apparatus, a tensioning device for tensioning the springs and including first and second shafts having respective end portions, and a housing for receiving the tensioning device therein, the housing including mutually adjacent narrow side walls for accommodating the first and second shafts of the tensioning device thereon, wherein the improvement comprises the first and second shafts mounted in said housing so as to cause the endportions of the first and second shafts respectively to project from said housing, said first and second springs being disposed outside of said housing and having respective one ends, and anchor means for anchoring said one ends of said springs to the housing at respective anchor locations, the other end of the first spring being connected to said end-portion of said first shaft so as to coact therewith and the other end of the second spring being connected to the end-portion of said second shaft so as to coact therewith, said first shaft and said anchor means conjointly supporting said first spring adjacent the outer side of one of said side walls, and said second shaft and said anchor means conjointly supporting said second spring adjacent the outer side of the other one of said side walls whereby said springs are arranged outside of the housing thereby rendering said springs accessible for inspection and maintenance work, the housing further including a center wall connecting the mutually adjacent narrow side walls and, two mutually parallel carrier rails to which the breaker and the switching pole can be securely mounted, said carrier rails being mounted on said center wall.
 2. In an actuating mechanism for an electric switching apparatus such as an electric circuit breaker or the like, said mechanism including first and second springs for respectively storing the energy needed for closing and the energy needed for opening the apparatus, a tensioning device for tensioning the springs and including first and second shafts having respective end portions, and a housing for receiving the tensioning device therein, the housing including mutually adjacent narrow side walls for accommodating the first and second shafts of the tensioning device thereon, wherein the improvement comprises the first and second shafts mounted at fixed locations in said housing so as to cause the end-portions of the first and second shafts respectively to project from said housing, said first and second springs being disposed outside of said housing and having respective one ends, and anchor means for anchoring said one ends of said springs to the housing at respective anchor locations, the other end of the first spring being connected to said end-portion of said first shaft so as to coact therewith and the other end of the second spring being connected to the end-portion of said second shaft so as to coact therewith, said first shaft and said anchor means conjointly supporting said first spring adjacent the outer side of one of said side walls, and said second shaft and said anchor means conjointly supporting said second spring adjacent the outer side of the other one of said side walls whereby said springs are arranged outside of the housing thereby rendering said springs accessible for inspection and maintenance work.
 3. In the actuating mechanism of claim 2, said first shaft being mounted in the housing at a first distance from the anchor location of the first spring, and said second shaft being mounted in the housing at a second distance from the anchor location of the second spring, said first distance being greater than said second distance.
 4. In the actuating mechanism of claim 3, wherein said anchor locations of said springs are at the same elevation on said housing. 